Chalcone synthase and flavonoid products in primary-leaf tissues of rye and maize

Jähne, A.; Fritzen, Claudia; Weissenböck, Gottfried

doi:10.1007/bf00201341

Cited by 23 publications

(6 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the case of the two tissue types, one factor that contributes to their separation by PCA is the presence and absence of flavonoids. Prior studies also have documented such developmental regulation of flavonoids and other maize metabolites (Jahne et al, 1993;Pick et al, 2011). It is likely that the more exposed position of leaf tips requires more flavonoids for defense against biotic and abiotic stress.…”

Section: Discussionmentioning

confidence: 97%

Metabolome-Scale Genome-Wide Association Studies Reveal Chemical Diversity and Genetic Control of Maize Specialized Metabolites

et al. 2019

View full text Add to dashboard Cite

Cultivated maize (Zea mays) has retained much of the genetic diversity of its wild ancestors. Here, we performed nontargeted liquid chromatography-mass spectrometry metabolomics to analyze the metabolomes of the 282 maize inbred lines in the Goodman Diversity Panel. This analysis identified a bimodal distribution of foliar metabolites. Although 15% of the detected mass features were present in >90% of the inbred lines, the majority were found in <50% of the samples. Whereas leaf bases and tips were differentiated by flavonoid abundance, maize varieties (stiff-stalk, nonstiff-stalk, tropical, sweet maize, and popcorn) showed differential accumulation of benzoxazinoid metabolites. Genome-wide association studies (GWAS), performed for 3,991 mass features from the leaf tips and leaf bases, showed that 90% have multiple significantly associated loci scattered across the genome. Several quantitative trait locus hotspots in the maize genome regulate the abundance of multiple, often structurally related mass features. The utility of maize metabolite GWAS was demonstrated by confirming known benzoxazinoid biosynthesis genes, as well as by mapping isomeric variation in the accumulation of phenylpropanoid hydroxycitric acid esters to a single linkage block in a citrate synthase-like gene. Similar to gene expression databases, this metabolomic GWAS data set constitutes an important public resource for linking maize metabolites with biosynthetic and regulatory genes.

show abstract

Section: Discussionmentioning

confidence: 97%

Metabolome-Scale Genome-Wide Association Studies Reveal Chemical Diversity and Genetic Control of Maize Specialized Metabolites

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Measurement of the UV-B penetration Transmission of monochromatic UV-B radiation (310 nm) into leaf tissues was measured using a quartz fibre optic microprobe with a tapered end of 10 jim diameter as described earlier (Cen and Bornman 1993), The 50% acceptance angle of the microprobe was 31 °, Since both epidermal layers showed the same potential of phenolic product accumulations (Jahne et al, 1993, Strack et al, 1982, measurements were only performed on the adaxial leaf side. Individual primary leaf segments (0,5-2,0 cm from the leaf tip) from 7-day-old plants were mounted in a leaf holder and placed with the adaxial surface facing the xenon arc source (Oriel, Stratford, CT, USA; 500 W) and a quartz lens was used to focus the coilimated beam (probe orientation 0°), Since this forward propagated radiation makes up most of the signal, only this component was measured in order to detennine relative differences between treatments.…”

Section: Figment Analysismentioning

confidence: 99%

Phenylpropanoid compounds in primary leaf tissues of rye (Secale cereale). Light response of their metabolism and the possible role in UV‐B protection

Reuber

Bornman

Weissenböck

1996

Physiologia Plantarum

View full text Add to dashboard Cite

Phenylpropanoid compounds in primary leaf tissues of rye {Secale cereale). Light response of their metabolism and the possible role in UV-B protection. -Physiol. Plant. 97; 160-168.The present study was undertaken in order to investigate the suitability of certain markers for UV plant response. In addition, we attempted to link the intemal tissue distribution of specific UV-absorbing compounds to profiles of radiation gradients within intact primary rye leaves {Secale cereale L, cv. Kustro), Etiolated rye seedlings irradiated wift low visible light (LL) and/or UV radiation were used to study enzyme activities of the two key enzymes, phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS), together with the tissue-specific accumulation of soluhle phenylpropanoid products. Plants grown under relatively high visible light (HL) with or without supplementary UV-B radiation were used for further characterization. Apparent quantum yield and fluorescence quenching parameters were monitored to assess potential physiological changes due to UV-B exposure in HL-grown seedlings. A quartz fibreoptic microprobe was used to characterize the intemal UV-B gradient of the leaf. The response of the phenylpropanoid metabolism to UV radiation was similar in primary' leaves of both etiolated and HL-treated green plants. The epidermis-specific fla-vOTioids together with CHS activity tumed out to be suitable markers for assessing the effect of UV on the phenolic metabolism. The functional role of phenyipropanoid compounds was strongly implicated in protecting rye from UV-B radiation.

show abstract

“…In primary leaves of rye, the distribution of epidermal flavonoids and HCAs is tissue-specific (Strack, Meurer & Weissenböck 1982;Schulz & Weissenböck 1986;Strack, Keller & Weissenböck 1987) and especially flavonoids are strongly light-inducible (Reuber et al 1996b;Haussühl, Rohde & Weissenböck 1996). During leaf development, cells of both the adaxial and abaxial epidermis accumulate a number of soluble HCA esters (primarily p-coumaric and ferulic acid) and two isovitexin-glycosides (R3 and R4), whereas the mesophyll contains two luteolin-glucuronides (R1 and R2) (Anhalt & Weissenböck 1992;Jähne, Fritzen & Weissenböck 1993). Under the influence of supplemental UV-B irradiation, epidermal flavonoids show a rapid and strong increase in concentration (Tevini et al 1991), whereas epidermal HCAs and mesophyll flavonoids show no or only a slight increase as compared to white light (Reuber et al 1996b).…”

Section: Introductionmentioning

confidence: 99%

Contribution of hydroxycinnamates and flavonoids to epidermal shielding of UV‐A and UV‐B radiation in developing rye primary leaves as assessed by ultraviolet‐induced chlorophyll fluorescence measurements

Burchard

Bilger²,

Weissenböck

2000

Plant Cell & Environment

261

196

View full text Add to dashboard Cite

tective compounds of the primary leaf. This function is increasingly replaced by the epidermal flavonoids during leaf development and acclimation. The application of chlorophyll fluorescence measurements has been proven to be a useful tool for estimating relative contents of these compounds in epidermal tissue.Key-words: Secale cereale L.; chlorophyll fluorescence; epidermal transmittance; flavonoids; hydroxycinnamic acid conjugates; leaf development; ultraviolet screening pigments. INTRODUCTIONAn unavoidable consequence of the exposure of plants to natural sunlight is the exposure to ultraviolet (UV) radiation. Radiation at wavelengths below 320 nm (UV-B, 290-320 nm) is principally damaging to DNA, proteins and other essential molecules, e.g. auxin (Jordan 1996;Taylor, Tobin & Bray 1997;Jansen, Gaba & Greenberg 1998).Plants have evolved two major strategies for resistance to UV-B radiation: (1) repair mechanisms (e.g. repair of DNA damages by excision repair or by repair of pyrimidine-dimers and other DNA photoproducts by specific enzymes such as photolyase, activated by UV-A and photosynthetically active radiation (PAR) (Taylor et al. 1997)); and (2) avoidance mechanisms (primarily epidermal screening of UV-B radiation to protect the mesophyll tissue of a leaf by the accumulation of UV-absorbing compounds in cell vacuoles and/or cell walls of the epidermis (Caldwell, Robberecht & Flint 1983;Hutzler et al. 1998)). It is widely accepted that flavonoids and hydroxycinnamic acid conjugates (HCAs) are the most efficient UV-B screening compounds because of their strong absorbance in this wavelength region and because their concentration in epidermal layers is significantly increased by UV-radiation (Tevini, Braun & Fieser 1991;Beggs & Wellmann 1994;Bornman et al. 1997) From the fourth to the tenth day after sowing, epidermally located flavonoids increased in an age-and irradiation-dependent manner, whereas mesophyll flavonoids and epidermal HCAs, mainly ferulic acid and p-coumaric acid esters, were constitutively present and did not vary in their contents over the observed time period. There was an excellent correlation between epidermal UV-A and UV-B absorbances as assessed by chlorophyll fluorescence measurements and contents of epidermal flavonoids. However, HCAs showed an additional contribution to UV-B shielding. In contrast, mesophyll flavonoids did not seem to play a respective role. When absorbances of the abaxial and adaxial epidermal layers were compared, it became apparent that in fully expanded primary leaves epidermal tissues from both sides were equally effective in absorption of UV-radiation. However, the earlier and more UV-exposed abaxial epidermis of young unrolling leaves showed a significantly higher absorption. It is shown that in early stages of development the epidermal HCAs are the dominant UV-B pro-

show abstract

Chalcone synthase and flavonoid products in primary-leaf tissues of rye and maize

Cited by 23 publications

References 35 publications

Metabolome-Scale Genome-Wide Association Studies Reveal Chemical Diversity and Genetic Control of Maize Specialized Metabolites

Metabolome-Scale Genome-Wide Association Studies Reveal Chemical Diversity and Genetic Control of Maize Specialized Metabolites

Phenylpropanoid compounds in primary leaf tissues of rye (Secale cereale). Light response of their metabolism and the possible role in UV‐B protection

Contribution of hydroxycinnamates and flavonoids to epidermal shielding of UV‐A and UV‐B radiation in developing rye primary leaves as assessed by ultraviolet‐induced chlorophyll fluorescence measurements

Contact Info

Product

Resources

About